Viral diseases are an increasing worldwide health concern.
HIV infection has been implicated as the primary cause of acquired immune deficiency syndrome (AIDS). Barre-Sinoussi et al. (1983) Science 220:868-870; and Gallo et al. (1984) Science 224:500-503. Infection of the CD4+ subclass of T-lymphocytes with the HIV-1 virus leads to depletion of this essential lymphocyte subclass which inevitably leads to opportunistic infections, neurological disease, neoplastic growth and eventually death. Anti-retroviral drugs, such as reverse transcriptase inhibitors, viral protease inhibitors, and viral entry inhibitors, have been used to treat HIV infection (Caliendo et al. (1994) Clin. Infect. Dis. 18:516-524). More recently, treatment with combinations of these agents, known as highly active antiretroviral therapy (HAART), has been used to suppress replication of HIV (Gulick et al. (1997) N. Engl. J. Med. 337:734-9 (see comments); Hammer et al. (1997) N. Engl. S. Med. 337:725-733). Viral hepatitis is a cause of considerable morbidity and mortality in the human population, both from acute infection and chronic sequelae which include, in the case of hepatitis B, C and D, chronic active hepatitis and cirrhosis. Promising classes of treatment agents for hepatitis include interferons (hepatitis B) and protease inhibitors (hepatitis C).